Toggle clamp with positive latch and clamp actuating handle

ABSTRACT

A toggle clamp includes a pivot base mountable upon a support with a pair of side plates adjustably mounted upon said pivot base in a pre-selected angular position and guidably receiving therebetween a pivot arm pivotally mounted upon said plates and terminating in a work piece engaging clamp arm. A U-shaped handle link is pivotally mounted over and upon the guide plates and pivotally mounts interiorly a pair of arm links at their one ends, with the other ends of said arm links pivotally connected to the handle link. A yieldable latch is positioned between the arm links and pivotally connected thereto and adapted to interlock with a latch plate spanning said guide plates when the handle link has been moved to a release position. The improvement comprises a latch handle secured to said latch. An operative handle is secured to the free end of the latch handle at any desired angle for disengaging said latch from the latch plate and for successive return movement of the clamp arm to workpiece securing position, and release position.

United States Patent [191 Blatt [451 *Apr. 1, 1975 TOGGLE CLAMP WITHPOSITIVE LATCH AND CLAMP ACTUATING HANDLE [76] Inventor: Leland F.Blatt, 31915 Groesbeck l-lwy., Grosse Point Shores, Mich. 48026 Notice:The portion of the term of this patent subsequent to Feb. 19, 1991, hasbeen disclaimed.

[22] Filed: Nov. 28, 1973 [21] Appl. No.: 419,611

Related U.S. Application Data [63] Continuation-in-part of Ser. No.326,899, Jan. 26, 1973, Pat. No. 3,792,853, which is acontinuation-in-part of Ser. No. 292,877, Sept. 28, 1972, Pat. No.3,782,712.

Primary Examiner-Roy Lake Assistant Examiner-Mark S. Bicks Attorney,Agent, or Firm-Cullen, Settle, Sloman & Cantor [57] ABSTRACT A toggleclamp includes a pivot base mountable upon a support with a pair of sideplates adjustably mounted upon said pivot base in a pre-selected angularposition and guidably receiving therebetween a pivot arm pivotallymounted upon said plates and terminating in a work piece engaging clamparm. A U-shaped handle link is pivotally mounted over and upon the guideplates and pivotally mounts interiorly a pair of arm links at their oneends, with the other ends of said arm links pivotally connected to thehandle link. A yieldable latch is positioned between the arm links andpivotally connected thereto and adapted to interlock with a latch platespanning said guide plates when the handle link has been moved to arelease position.

The improvement comprises a latch handle secured to said latch. Anoperative handle is secured to the free end of the latch handle at anydesired angle for disengaging said latch from the latch plate and forsuccessive return movement of the clamp arm to workpiece securingposition, and release position.

9 Claims, 2 Drawing Figures TOGGLE CLAMP WITH POSITIVE LATCH AND CLAMPACTUATING HANDLE RELATED APPLICATIONS This application is acontinuation-in-part of my copending application, Ser. No. 326,899 filedJan. 26, 1973, now US. Pat. No. 3,792,853 dated Feb. 19, 1974. Thelatter application is a continuation-in-part of my copending patentapplication, Ser. No. 292,877 filed Sept. 28, 1972, now U.S. Pat.3,782,712 dated Jan. 1, 1974 entitled TOGGLE CLAMP WITH DE- TENT OPENGUIDED ARM.

BACKGROUND OF THE INVENTION Toggle clamps are known to include upon abase a pivotal clamp arm with a suitable handle link pivotally mountedupon a base with additional linkage which pivotally engages the clamparm for moving the same from workpiece securing position to a retractedworkpiece release position.

Examples of such toggle clamps are shown in my US. Pat. Nos.: 3,009,6943,010,171 2,972,476 3,035,831.

BRIEF DESCRIPTION OF THE INVENTION The present invention is directed toan improved latch actuating handle for a toggle clamp which includes ayieldable latch mounted upon a handle link assembly adapted forinterlock with a stationary latch plate for anchoring a clamp arm inclamp-release posi tion. A latch handle is secured to the latch and anoperative handle is secured to the latch handle at any desired angle.

It is an object of the present invention to employ the operative handleto control pivotal movements of the latch and reciprocal opening andclosing movements of the clamp arm.

IN THE DRAWING FIG. I is a fragmentary side elcvational view of thepresent toggle clamp with the release position of the latch handle andclamp arm shown in dash lines;

FIG. 2 is a left end elevational view thereof.

The above drawing illustrates a preferred embodiment of the invention.Other embodiments are contemplated within the scope of the claimshereafter set forth.

DETAILED DESCRIPTION Referring to the drawing, clamp 11 includes a pivotbase 13 anchored by fasteners 15 to a suitable support F or fixture ormounting surface as fragmentarily shown, FIG. 1, and supporting workpiece W. A pair of upright opposed and spaced guide plates I7 and 19each having corresponding arcuate end faces 21 is pivotally mountedinitially by pivot pin 4] or bolt upon opposite sides ofthe base 13 andaffixed thereto in the desired position of angular adjustment by thewelds 23.

Transversely arranged latch plate 25 is selectively positioned acrossplates 17 and 19 at the desired angle and secured in position by thewelds 27. The latch plate has been located so as to yieldably retain thehandle assembly when it has been moved to the retracted release positionshown in dotted lines.

Pivot arm 29 is guidably and movably positioned between plates I7 and 19and pivotally mounted thereon upon the pivot pin 33 with bushing 31interposed and nested within an end portion of said pivot arm. The

pivot arm extends laterally outward from said guide shown in operativeclamping position with respect to work piece W upon the support F.

The inverted U-shaped handle link 37 is guidably positioned overopposite outer surfaces of the plates 17 and 19 and at its lower endspivotally mounted upon bolt 41 hereafter referred to as a first pivotpoint. The pivotal mounting of pivot arm 29 as at 33 is referred to as asecond pivot point.

Bolt 41 is anchored upon the guide plates 17 and 19 with a suitable nut43, FIG. 2. A pair of spaced arm links 45,47 are arranged upon theinterior of the handle link coplaner with the respective guide plates 17and I9 and pivotally connected to the handle link by transverse pin 49.Latch 51 is interposed between said arm links at their upper ends andpivotally mounted on the same pivot pin 49. This is the third pivotpoint.

The lower ends of the arm links engage opposite sides of the pivot arm29 and are pivotally connected thereto by the transverse pin 53,referred to the fourth pivot point. Latch 51 upon one side has a lateralprojection or stop 55 adapted to bear against a portion of the handlelink 37 under the bias of the coil spring 57. The latter is nestedwithin socket 59 in said latch and at its opposite end bears against aportion of the handle link, FIG. 1.

The transverse notch 61 formed in the outer surface of the latch has arear angle face 63. Upon retraction of the handle link 37 to clamp armrelease position, the latch slot 61 is adapted for selective registrywith latch plate 25, as shown in dash lines, FIG. I. Said latch platehas a front angle face 65 adapted for cooperative registry with latchrear angle face 63, for a snap interlock therewith.

The latch plate may be selectively positioned along the arcuate edges ofthe guide plates and affixed thereto for stablizing the assembly andspacing between the plates 17 and 19, and for yieldably retaining thehandle assembly when the clamp arm has been moved to a release positionshown in dash lines in FIG. I. In the solid line work securing position,pivot point 3 at 49 has moved across dead center with respect to pivotpoints I and 4; namely, the pivots 41 and 53 of FIG. 1 when the clamparm 36 is in its work piece securing position. The. angular movement ofretraction of the clamp arm can be set at to depending upon the locationof latch plate 25 and its securing to guide plates 17 and 19.

Since the latch notch 61 includes rear angle face 63 adapted for snuginterlock with respect to front angle face 65 of the latch plate 25,there is a positive securing or snubbing action as the handle link 37 ismoved from the solid line position in FIG. I to the dash line releaseposition. Here the latch 51 is hooked onto latch plate 25, serving twopurposes. It acts a snubbing action when the handle link has been movedto open position, and after latching, maintains zero play between rearangle face 63 of the latch and front angle face 65 of the latch plateto, thus, maintain a tight hooking contact.

DETAILED DESCRIPTION OF THE INVENTION In order to release the latch fromthe latch plate, there is provided latch handle 69. Said handle is apart of and extends outwardly of latch 51. Said latch handle has a freeend 75 spherical in shape. Operative handle 77 at one end has aspherical socket 79 for registry with the free end 75. Said operativehandle is set by the user to any desired angle relative to the latchhandle and secured thereto by welds 81. One such angle is shown in FIG.2. Said operating handle may be inclined laterally at an acute anglewith respect to the plane of movement of the latch in the range of to 60upon opposite sides thereof.

In view of the spring bias and pivotal mounting of latch 51, on fullretracting movement of operating handle 77 to the dash line releaseposition shown, there will be an automatic engagement of latch 51 withlatch plate 25.

A pre-stop block 83, FIG. 2, interconnects plates 17 and 19 forwardly ofthe pivotal connection 33 of the pivot arm. Adjustable set screw 85extends through said block and is adjusted to apply pressure to pivotarm 29. This removes all shake of tolerance in the mechanism, causingclamp arm 35 to be in a stable noshake or stationary position.

OPERATION The present latch 51 and the latch handle 69 are soconstructed and arranged that upon normal movement of the operatinghandle 77 in a counterclockwise direction from the dash line positionshown, FIG. 1, will first pivot the latch so as to disengage the latchfrom the latch bar 25. Continued successive movement in the samedirection of the operative arm 77 will rotate the clamp arm 35 to thework piece securing position shown in FIG. I.

Thereafter successive retraction or rotation of the operative handle 77in the opposite direction, i.e., clockwise, will in effect retract thepivot arm and connected clamp arm 35 to the dotted line release positionshown. In this position, the latch 51 due to its spring bias 57 willagain snap lock with respect to the latch plate 25 holding the assemblyincluding the pivot arm in such retracted release position.

Accordingly, it appears that the operative handle 77, being the solehandle for manual application, is arranged at the desired angle normallylaterally of the path of rotation of the latch handle 69 such as shownin FIG. 2. Additionally, the single operative handle 77 is adapted foreffecting manual release or disengaging movements of the latch withrespect to the latch plate 25 and, furthermore, is adapted to controlswinging movements of the clamp arm to the operative position shown inFIG. I or to the retracted dotted line release position shown.

The latch handle 69 is so arranged with respect to the handle link thatafter initial rotation of the operative handle 71 in a counterclockwisedirection, the latch handle will operatively engage the handle link soas to effect rotation thereof to the work piece securing position shownin FIG. 1.

Having described my invention, reference should now be had to thefollowing claims.

I claim:

I. In a toggle clamp having a pivot base mountable upon a support; apair of upright parallel spaced guide plates secured upon said pivotbase in a pre-selected angular position; a pivot arm guidably positionedbetween said plates and at one end pivotally mounted upon said platesand terminating in a clamp arm adapted to retainingly engage a workpieceon said support; a U-shaped handle link overlying said guide plates andat its free ends pivotally mounted upon said side plates; a pair ofspaced arm links at their one ends pivotally mounted upon said handlelink coplaner with said guide plates, and at their lower ends engagingopposite sides of and pivotally connected to said pivot arm; a latchbetween said arm links at their upper ends and pivotally mounted uponsaid handle link; said latch having a transverse detent notch; a latchplate transversely spanning and connected to the outer side edges ofsaid guide plates; said latch notch on retracting movement of saidhandle link yieldably receiving said latch plate anchoring the handlelink in a retracted release position; the improvement comprising:

a latch handle on said latch; and an operating handle at one end securedat a preselected angle to the end of said latch handle, in a -planetransverse to the plane of movement of the latch, adapted to manuallyrotate said latch to disengage it from the latch plate; and furtheradapted on rotation in a counterclockwise direction to rotate said clamparm into workpiece securing position, and successively in the oppositedirection, to rotate said clamp arm and latch to a retracted releaseposition.

2. In the toggle clamp of claim 1, resilient means biasing said latchagainst said handle link.

3. In the toggle clamp of claim 1, said guide plates being pivotallyadjusted initially at a first pivot point upon said base; the mountingof said pivot arm being at a second pivot point said plates; themounting of said arm links at their one ends being at a third pivotpoint upon said handle link, and the connection at their other ends tosaid pivot arm being at a fourth pivot point; the latch mounting beingat said third pivot point.

4. In the toggle clamp of claim 3, said guide plate outer side edgesbeing arcuate at a fixed radius to said first pivot point; said latchplate being selectively positioned along said outer side edges andsecured thereto depending upon the desired arc of release retraction ofsaid first handle.

5. In the toggle clamp of claim 3, said third pivot point passing deadcenter with respect to said first and fourth pivot points when saidfirst handle has moved the clamp arm to work piece securing position.

6. In the toggle clamp of claim 1, said latch plate having an undercutfront angle face; said latch notch including a rear angle face forcooperative interlock therewith.

7. In the toggle clamp of claim 1, said operating handle being inclinedlaterally at an acute angle with respect to the plane of movement ofsaid latch handle in the range of 0 to 60 upon opposite sides thereof.

8. In the toggle clamp of claim 1. a pre-stop block interposed betweenand secured to said guide plates forwardly of the pivotal mounting ofsaid pivotal arm; and an adjustable set screw threaded through saidblock adapted to apply a stabilizing pressure to said pivotarm, toremove all shake due to tolerance in the assembly.

9. In the toggle clamp of claim 7, one end of said latch handle being ofspherical shape; the corresponding end of said operative handle having aspherically shaped socket cooperatively receiving said latch handle.

1. In a toggle clamp having a pivot base mountable upon a support; apair of upright parallel spaced guide plates secured upon said pivotbase in a pre-selected angular position; a pivot arm guidably positionedbetween said plates and at one end pivotally mounted upon said platesand terminating in a clamp arm adapted to retainingly engage a workpieceon said support; a Ushaped handle link overlying said guide plates andat its free ends pivotally mounted upon said side plates; a pair ofspaced arm links at their one ends pivotally mounted upon said handlelink coplaner with said guide plates, and at their lower ends engagingopposite sides of and pivotally connected to said pivot arm; a latchbetween said arm links at their upper ends and pivotally mounted uponsaid handle link; said latch having a transverse detent notch; a latchplate transversely spanning and connected to the outer side edges ofsaid guide plates; said latch notch on retracting movement of saidhandle link yieldably receiving said latch plate anchoring the handlelink in a retracted release position; the improvement comprising: alatch handle on said latch; and an operating handle at one end securedat a pre-selecteD angle to the end of said latch handle, in a planetransverse to the plane of movement of the latch, adapted to manuallyrotate said latch to disengage it from the latch plate; and furtheradapted on rotation in a counterclockwise direction to rotate said clamparm into workpiece securing position, and successively in the oppositedirection, to rotate said clamp arm and latch to a retracted releaseposition.
 2. In the toggle clamp of claim 1, resilient means biasingsaid latch against said handle link.
 3. In the toggle clamp of claim 1,said guide plates being pivotally adjusted initially at a first pivotpoint upon said base; the mounting of said pivot arm being at a secondpivot point said plates; the mounting of said arm links at their oneends being at a third pivot point upon said handle link, and theconnection at their other ends to said pivot arm being at a fourth pivotpoint; the latch mounting being at said third pivot point.
 4. In thetoggle clamp of claim 3, said guide plate outer side edges being arcuateat a fixed radius to said first pivot point; said latch plate beingselectively positioned along said outer side edges and secured theretodepending upon the desired arc of release retraction of said firsthandle.
 5. In the toggle clamp of claim 3, said third pivot pointpassing dead center with respect to said first and fourth pivot pointswhen said first handle has moved the clamp arm to work piece securingposition.
 6. In the toggle clamp of claim 1, said latch plate having anundercut front angle face; said latch notch including a rear angle facefor cooperative interlock therewith.
 7. In the toggle clamp of claim 1,said operating handle being inclined laterally at an acute angle withrespect to the plane of movement of said latch handle in the range of 0*to 60* upon opposite sides thereof.
 8. In the toggle clamp of claim 1, apre-stop block interposed between and secured to said guide platesforwardly of the pivotal mounting of said pivotal arm; and an adjustableset screw threaded through said block adapted to apply a stabilizingpressure to said pivot arm, to remove all shake due to tolerance in theassembly.
 9. In the toggle clamp of claim 7, one end of said latchhandle being of spherical shape; the corresponding end of said operativehandle having a spherically shaped socket cooperatively receiving saidlatch handle.